The pleasure of cigarette smoking emits cigarette smoke commonly referred to as secondary cigarette smoke which some people find objectionable. Cigarette smoker's in consideration of these people, have taken steps to avoid smoking in areas where secondary smoke may be found to be objectionable. In addition, in certain jurisdictions restrictions have been introduced to ensure that secondary smoke is not generated in defined areas. Such restrictions include designated "no smoking" areas and the use of expensive room ventilation systems and the like to minimize secondary smoke. There is a significant need for a smoker's device which would allow the smoker to enjoy the pleasure of smoking without generating secondary smoke and affecting others who might find it objectionable.
Secondary smoke is generated in a number of ways during the smoking process. Secondary smoke is principally comprised of sidestream smoke which is generated by a burning cigarette between puffs. Other contributions to sidestream smoke include mainstream smoke spillage from the smoker's mouth and exhaled smoke. A number of prior proposals have been made with respect to structures designed to minimize or eliminate the formation of secondary smoke. Such prior proposals have tackled the major source of cigarette smoke, namely the sidestream smoke and exhaled smoke and to some extent the mainstream smoke spillage. Various prior art efforts have been made to either capture in some form of container, secondary smoke or to filter secondary smoke before release to the surroundings. Examples of such prior devices are described in U.S. Pat. Nos. 4,198,992; 4,200,114; 4,637,407; 4,790,332; 4,899,766; 4,993,435; 5,048,845; 5,160,518; 5,497,791; 5,495,859 and Japanese application HEI3-177280 published Apr. 27, 1993.
Several of these devices employ fans with filter arrangements or container systems to trap secondary smoke before it is released to the surroundings. Usually the fan arrangements are designed to capture the major component of secondary smoke, namely, sidestream smoke. The fan arrangements are designed to draw sidestream smoke from the burning end of the cigarette in a direction pointing away from the cigarette tip. Examples of such devices are described in the above namely, U.S. Pat. Nos. 4,637,407; 4,899,766; 5,048,545 and 5,497,791. Although systems offered by these U.S. Patents provide varying degrees of success in eliminating sidestream smoke, U.S. Pat. Nos. 4,899,766 and 5,048,545 are not hand-held, that is, the entire system is far too bulky to be carried around. The systems of U.S. Pat. Nos. 4,637,407 and 5,497,791 are hand-held but bring with the design, due to its compact nature, significant design constraints in order to achieve sidestream smoke filtration. The system of U.S. Pat. No. 5,497,791 is very effective in this regard but presents certain design restrictions in achieving sidestream smoke filtration, such as build-up of heat in the filter system and the momentary resistance to sidestream smoke flow over the burning ash during each puff on the cigarette.
It is therefore an object of an aspect of this invention to provide a combustion chamber for a hand-held cigarette smoke filtering device for filtering sidestream smoke in a very efficient manner while taking advantage of the normal direction of flow of cigarette smoke towards the cigarette tip during the smoking process as well as the natural rise of heat from the cigarette. It is also an object of an aspect of the invention to provide a filter design which inherently cools the sidestream smoke before it passes through the filter system. In accordance with an aspect hereof, a plenum may be used to connect combustion chamber to sidestream filter. It is also another object of an aspect of the design to provide a sidestream smoke filtration system which avoids the collection of cigarette ash in the filter system.